Noise Pollution

Measurement

A decibel is the standard for the measurement of noise. The zero on a decibel scale is at the threshold of hearing, the lowest sound pressure that can be heard, on the scale acc. To smith, 20 db is whisper, 40 db the noise in a quiet office. 60 db is normal conversation, 80 db is the level at which sound becomes physically painfull.

The Noise quantum of some of the cities in our country indicate their pitch in decibel in the nosiest areas of corresponding cities, e.g. Delhi- 80 db, Kolkata - 87,Bombay-85, Chennai-89 db etc.

On the basis of measurement noise pollution can be divided into following type

Sounds of normal conversation:Sound Intensity: 40-60 dbHealth Hazard: Sound, less than 80 db, is safe for the ear.

Sounds emanting from tape recorders or an orchestra:Sound Intensity : 70 dbHealth Hazard : It is safe for ear.

Sounds of rockets during take off:Sound Intensity: 200 dbHealth Hazard: It is dangerously causing total deafness by rupturing the eardrums and damaging the inner ear. It also causes high blood pressure, ulcer in stomach, palpitation, nervous problems, irritation, anger and affects pregnant women’s embryo.